sanic-org Sanic up to 24.12.0/25.12.0 HTTP/1.1 Chunked-Body input validation

Summaryinfo

A vulnerability was found in sanic-org Sanic up to 24.12.0/25.12.0. It has been classified as critical. This impacts an unknown function of the component HTTP1.1 Chunked-Body Handler. The manipulation leads to input validation. This vulnerability is documented as CVE-2026-85078. The attack can be initiated remotely. There is not any exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in sanic-org Sanic up to 24.12.0/25.12.0 and classified as critical. This issue affects an unknown code block of the component HTTP1.1 Chunked-Body Handler. The manipulation with an unknown input leads to a input validation vulnerability. Using CWE to declare the problem leads to CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. Impacted is integrity, and availability. The summary by CVE is:

Sanic is an opensource python web server/framework. In version 25.12.0, Sanic's core HTTP/1.1 chunked-body handling does not fully consume the trailer-part after the terminating zero chunk before reusing the keep-alive connection buffer. A remote unauthenticated client can place attacker-controlled bytes in that trailer region, causing Sanic to parse and route them as a hidden second request after the outer request. This breaks HTTP request-boundary integrity and can provide a request-smuggling primitive when Sanic is deployed behind intermediaries. This issue is fixed in version 25.12.1.

The advisory is shared at github.com. The identification of this vulnerability is CVE-2026-85078 since 09/02/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Neither technical details nor an exploit are publicly available.

Upgrading to version 24.12.1 or 25.12.1 eliminates this vulnerability.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

• sanic-org

Name

• Sanic

Version

• 24.0
• 24.1
• 24.2
• 24.3
• 24.4
• 24.5
• 24.6
• 24.7
• 24.8
• 24.9
• 24.10
• 24.11
• 24.12.0
• 25.0
• 25.1
• 25.2
• 25.3
• 25.4
• 25.5
• 25.6
• 25.7
• 25.8
• 25.9
• 25.10
• 25.11
• 25.12.0

Website

• Product: https://github.com/sanic-org/sanic/

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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